Angular 2 Tutorial,路由部分未处理的承诺拒绝

Question

我正在尝试遵循官方教程.一切顺利,直到这里的路由部分.当我到达我们重新制作app.component.ts并更改app.module.ts的部分时,我在localhost上获得了一个加载屏幕,控制台错误是:

未处理的Promise拒绝:模板解析错误:无法绑定到'hero',因为它不是'my-hero-detail'的已知属性.

我确保通过从这里复制粘贴相关文件,这可能是我之前在教程中所犯的错误.该项目的工作原理与喷射器完全相同.

我的问题是什么导致承诺失败,当它在早期版本中工作,我在哪里可以学习如何解决它？

代码摘录:

来自app.component.ts

import { Component, OnInit } from '@angular/core';

import { Hero } from './hero';
import { HeroService } from './hero.service';

@Component({
selector: 'my-heroes',
template: `
<h1>{{title}}</h1>
<h2>My Heroes</h2>
<ul class="heroes">
  <li *ngFor="let hero of heroes"
    [class.selected]="hero === selectedHero"
    (click)="onSelect(hero)">
    <span class="badge">{{hero.id}}</span> {{hero.name}}
  </li>
</ul>
<my-hero-detail [hero]="selectedHero"></my-hero-detail>
`,

...

export class HeroesComponent implements OnInit {
title = 'Tour of Heroes';
heroes: Hero[];
selectedHero: Hero;

constructor(private heroService: HeroService) { }

getHeroes() {
this.heroService.getHeroes().then(heroes => this.heroes = heroes);
}

ngOnInit() {
  this.getHeroes();
}

onSelect(hero: Hero) { this.selectedHero = hero; }
}

来自app.component.ts

import { Component } from '@angular/core';
@Component({
  selector: 'my-app',
  template: `
    <h1>{{title}}</h1>
    <my-heroes></my-heroes>
  `
})
export class AppComponent {
  title = 'Tour of Heroes';
}

来自app.module.ts

import { NgModule }       from '@angular/core';
import { BrowserModule }  from '@angular/platform-browser';
import { FormsModule }    from '@angular/forms';
import { AppComponent }   from './app.component';
import { HeroesComponent }  from './heroes.component';
import { HeroService }  from './hero.service';
@NgModule({
  imports: [
    BrowserModule,
    FormsModule
  ],
  declarations: [
    AppComponent,
    HeroesComponent
  ],
  providers: [
    HeroService
  ],
  bootstrap: [ AppComponent ]
})
export class AppModule {
}

来自hero-detail.component.ts

import { Component, Input } from '@angular/core';
import { Hero } from './hero';

@Component({
  selector: 'my-hero-detail',
  template: `
    <div *ngIf="hero">
      <h2>{{hero.name}} details!</h2>
      <div>
        <label>id: </label>{{hero.id}}
      </div>
      <div>
        <label>name: </label>
        <input [(ngModel)]="hero.name" placeholder="name"/>
      </div>
    </div>
  `
})
export class HeroDetailComponent {
  @Input() hero: Hero;
}

已编辑以修复plunkr链接

Answer 1

我在教程后面得到了同样的错误.他们可能错过了一点变化app.module.ts.在HeroDetailComponent尚未导入并添加到阵列的声明.因此hero,该组件的属性未知.

添加导入以及相应的声明应解决此问题:

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule }   from '@angular/forms';

import { AppComponent }  from './app.component';

import { HeroesComponent } from './heroes.component';
import { HeroDetailComponent } from './hero-detail.component';

import { HeroService } from './hero.service';

@NgModule({
    imports: [
        BrowserModule,
        FormsModule
    ],
    declarations: [
        AppComponent,
        HeroesComponent,
        HeroDetailComponent
    ],
    providers: [
        HeroService
    ],
    bootstrap: [AppComponent]
})
export class AppModule { }

我假设他们忘记记录这一变化.如果您查看下一章(https://angular.io/docs/ts/latest/tutorial/toh-pt6.html),您会在app.module.js文件中找到此更改.

Answer 2

如果你读下几段(更像是30段),你会看到

使用<my-hero-detail>标记删除模板的最后一行.

这将停止该错误

我现在正在阅读教程,实际上是在寻找答案哈哈